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Activity Number:
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123
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Type:
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Contributed
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Date/Time:
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Monday, August 3, 2009 : 8:30 AM to 10:20 AM
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Sponsor:
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Biopharmaceutical Section
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| Abstract - #305011 |
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Title:
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Modeling Heterogeneity and Its Effect on Design Parameters in Phase II Clinical Trials
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Author(s):
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Christopher N. Barnes*+ and Shesh N. Rai
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Companies:
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University of Louisville and University of Louisville
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Address:
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Delia B. Baxter Biomedical Research Building, Louisville, KY, 40292,
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Keywords:
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Heterogeneity ; Power analysis ; Phase II
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Abstract:
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The homogeneity assumption of a phase II single arm binary clinical trial is commonly violated due to lack of fit of population profile estimates or patient accrual causing Simon's 2-stage design parameters to be violated. Using a general framework to model heterogeneity through heterogeneity classes and heterogeneity imbalance, we investigate the effects of heterogeneity on the operating characteristics of the Simon Phase II clinical trial design using the standard practice of averaging a response profile. We show that under heterogeneity, the Simon designs have unacceptable probabilities of being underpowered or oversized, irrespective of the response profile, under the averaging practice. We propose an adaptive modification to the Simon design to improve its performance.
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